Wednesday, June 9, 2010

Orange Azalea (Rhododendron austrinum)

I’ve identified this shrub as Rhododendron austrinum (Orange Azalea, Florida Flame Azalea or Yellow Azalea) based on the color of the bloom and the morphology of the stamens. I know of only one shrub in Fort Yargo State Park and it is growing in an area not accessible from trails. It can be seen from the water (segment 9).

The shrub in bud

A bud, up close. In the background, leaves have emerged but are not fully developed.

The shrub in flower – from out on the water.

A little closer. The long, curved stamens are visible, even at a distance.

A closer view of the flowers. The long, curved stamens are quite apparent.

The fully developed leaves

There are two orange azalea species that may occur naturally in Georgia. One species is Rhododendrum austrinum – the Orange Azalea or Florida Flame Azalea – which is found only in Florida, Georgia, Alabama, and Mississippi. The other species is Rhododendron calendulaceum – the Flame Azalea – which is found in the southeastern states from New York south to Mississippi and in all states east with the exception of Florida. More detailed maps indicate that Rhododendron calendulaceum is found more frequently in the Blue Ridge mountrains including counties in north Georgia and Rhododendron austrinum is found more frequently in the Gulf Coast counties in southern Mississippi, Alabama, Florida, and in southwestern Georgia counties (see Distribution Maps)

So the observation of this shrub in Fort Yargo State Park is a little south of the range for naturally occurring Rhododendron calendulaceum and north of the range for Rhododendron austrinum. However, the morphology of the stamens – long and curved is similar to Rhododendron austrinum rather than shorter and straighter than those of Rhododendron calendulaceum.Click on an image to view a larger image